My newly aquired '82 242 GLT has an oil pressure gauge that pegs at full deflection whenever the ignition is on. From another post here I've learned that

"The oil pressure gauge will peg at the top if it does not get a ground signal from the sender. ie no resistance = top of gauge, direct ground on "G" terminal = a 0 bar reading"

I've been trying to figure out how to get at the back of the gauge and the Haynes manual is NO HELP (still trying to find a Bentley without waiting for mailorder ... I should have ordered it a week ago. It would be here by now!)

Before I break something, can someone give me a hint as to how to get to the back of the gauges?

Mark.

OK, Let me recap what I know so far.

1) with everything connected, 3-bar guage shows 3 bar. (full deflection)

1) wiring looks/feels intact and secure as far as I can follow it under the hood.

2) wiring looks/feels intact and secure as far as I can follow it behind the gauge.

3) grounding G terminal at guage shows 0 bar

4) grounding green wire at sender shows 0 bar

Conclusion? Bad Sender.

Do you concur?

The sender Dave suggested is a 5 bar sender. I didn't see a 3 bar sender on egauges.com I've also check some of the volvo parts sites I could find. Can you guy suggest a place to find the sender I need?

P.S. When you're goofing with the sender wiring after driving home from work, be careful of the hot manifold or you'll end up with blisters on the back of your hand.... Ask me how I know :)

Hmmmm, I just realized 3 bar gauge will read 0 to approx 45 psi. Does that mean this engine is not expected to produce more than 3 bar of oil pressure? that seems low for cold pressure in comparison to the other engines I know.

Sorry I assumed you had a 5 bar gauge, 3 bar would be ~ 45psi, egauges does not carry that. If you want a good used 5 bar sender and gauge contact me off list. $25 for both including shipping.
--
Dave Shannon
Spring Valley, California
'88-240 190K+
'65 1800S ????K
'73 1800ES 117K
'92 745Ti 160K
Jeep Wrangler Sahara 19K
my pages

Dave, email should be in your inbox.

Mark.

My 3bar guage is almost always pegged; up until i am about 2000 mi into the service cycle, then it starts dropping to about 2.5 at idle. Around 3000 mi, it's down to about 2bar at idle (and thats when my oil gets changed).
--
80 262C Coupe- (FSO black, M46, original) 82 244GLT- (auto)

I read your post to mean that your gauge always reads at 3bar all the time. This indeed probably means one of the wires has fallen off. They are on top of the pressure sender, just under the #1 exhaust manifold runner, behind the alternator. The wire connections are very easy to reach, unless you have very large hands. I bet the wire closest to you has fallen off. Lightly crimp the connecter and put back on.

I did this this morning on my '82 GLT!

good luck

Yes, that is exactly my problem .... except that the connections at the sender are secure.

Here's a pic of the problem sitting in the drivers seat. 3 bar all the time. If the ignition is off you can tap the gauge and it'll fall back to 0 but ignition on and it snaps back to 3 bar.

(I know you didn't need to see the pic but doesn't the GLT console look great!)



I'll be checking the gauge connections tonight and report back.

Mark.

Damn! I was hoping you had the "easy" problem! How do the wires look? I have the dreaded wire insulation rot: I put heat shrink wrap around the ends of the wires. Too afraid to open up the harness! Everything works, though.

You can always put a standard 2" oil gauge in the dash. remove the sending unit (behind the alternator) and use a metric adapter (from Autozone, spit, spit) to put a 1/8 copper line from that port to the back of the gauge. I have a factory looking installation and no idiot light blinking because of damaged wiring. The light wire goes to the instrument light dimmer. Just 38psi at idle and 55psi at speed. This from an 86 245 with 202k on the odometer.

Will
www.willdallas.org

And then you have hot, pressurized oil running into the cabin. No thanks.

Fixing the electrical problems should be pretty easy.. save for the delicate sender and adapters.

--
alex

When the owner of any vehicle wants to know what is going on with his engine, the gauges are aways mechanical. I'm 56 years old and hve been building custom rides since my teens, Included are several dozen 400+ hp engines for serious street and off shore applications. I never used an idiot light (wonder where they came up with that name?) on any of mine and have never, repeat never had a line break in the cab of my truck, car, or boat; nor seen a line break in 40 years of running everything from drag lines to dragsters, tug boats, charter boats, semis, and (sigh) Volvos.

(No offense intended)

WIll
www.willdallas.org

3)Here is the best way through the firewall. Hope these help.

Installation was around $40.00 with the gauge, and took about 2 hours.

Will
www.willdallas.org

2)Here is the sender unit replaced.

Will
www.willdallas.org

1)I thought that I would give you an illustration of the installation of the mechanical gauge in three parts.

Will
www.willdallas.org

More likely the wire at the sender is off and grounding to the block (look behind the alternator for the sender). If you can't get to the back of the gauge, maybe you should not be doing this.

"If you can't get to the back of the gauge, maybe you should not be doing this."

I thought this was going to be a nice place....

Robert, If you read my post (and my introduction) you will see that I DO know what I'm doing. I'm just new to this car and have yet to aquire the manual.

I've broken enough dash facia and plastic bezels to know that randomly yanking on trim is a BAD IDEA. I simply asked how the gauges come down.

Dave answered my question (Thanks Dave)

Robert, Maybe you're the kind of guy that will just "rip at the parts till it comes apart" but I'm not.

If you must make comments about others abilities, you should wait till you know them first.

Mark.

Sorry if that seemed harsh to you. We do get a lot of babysitting questions from some who seem to never figure anything out. Sometimes the list seems to be made up of 12 guys who have tried and learned, one way or another, and a whole lot of needy people who want to be told the simplest things. Nevertheless, if my advice is unsatisfactory, as always, I cheerfully refund what it cost. I have done my share of helping on this Board for many years, and yes, sometimes I am short with some questions. Big deal, it is just like conversation in real life to me.

Not to prolong the off topic conversation but...

I too have spent many years helping on boards such as this one. I fully understand that some people wnat to be told the simplest things. Being new to this board I took extra care in asking my first question here to explain my situation. If you re-read the question you will see that I did as much research on the board as I could. I explained that I knew this was a 'newbie' question and that I was concerned about damaging the "delicate bits" that are the facia.

I'm not quibbling with the reply -- "check the sender end" --
That was good advice (and I had already done that) I'm just suggesting that the comment about my (potential/uknown) mechanical abilities was absolutely un-called for given the question and my earlier introduction.

It IS just like real conversation in real life. If you'd said "maybe you shouldn't be doing that if you can't figure it out on your own" in person, we'd be having the same conversation.

Mark

Mark.

Bob,
He's talking about a gauge not the light, if it was grounded it would stay at 0. Pegging at the top of the gauge indicates infinite restance or close to it.
--
Dave Shannon
Spring Valley, California
'88-240 190K+
'65 1800S ????K
'73 1800ES 117K
'92 745Ti 160K
Jeep Wrangler Sahara 19K
my pages

Then, broken wire at sender?

Pull the bezel off of the gauge (probably a clock) just to the left of the 3 gauges. There are 2 screws that hold the 3 gauge mounting bracket in, remove them and pull the left side out, this will unhook the right side and the 3 gauge cluster will pull out.

Check resistance between the green wire that goes to the oil gauge and a good ground. Resistance should be darn near 0 with the engine off. If you have infinite resistance hope for a loose wire up at the oil pressure sender up under the exhaust just above the oil filter.

If no loose wire get new sender and replace it. egauges.com #360 009 Be very carefull of the 45 degree fitting, they get old and tend to snap off.
Good luck.


--
Dave Shannon
Spring Valley, California
'88-240 190K+
'65 1800S ????K
'73 1800ES 117K
'92 745Ti 160K
Jeep Wrangler Sahara 19K
my pages